IPv4 Subnet Calculator

Enter an IP with a CIDR prefix or a subnet mask to see its network, broadcast, host range, and host count. You can also split the network into smaller subnets.

Try:192.168.1.10/24 10.0.0.0/8 172.16.5.4/20 203.0.113.9/29

IPv6 calculator →

private IP (RFC 1918)10.0.240.0/21

network10.0.240.0/21

broadcast10.0.247.255

first host10.0.240.1

last host10.0.247.254

subnet mask255.255.248.0

wildcard0.0.7.255

addresses2,048

usable hosts2,046

classA

ipcalc 10.0.240.0/21

address00001010.00000000.11110000.00000000

subnet mask11111111.11111111.11111000.00000000

network00001010.00000000.11110000.00000000

broadcast00001010.00000000.11110111.11111111

green = network part, grey = host part

hex0x0a00f000

decimal167833600

reverse dns0.240.0.10.in-addr.arpa

ipv4-mapped::ffff:a00:f000

/21 split into /29 · 256 subnets

close ×

#	network	host range	broadcast
1	10.0.240.0/29	10.0.240.1 – 10.0.240.6	10.0.240.7
2	10.0.240.8/29	10.0.240.9 – 10.0.240.14	10.0.240.15
3	10.0.240.16/29	10.0.240.17 – 10.0.240.22	10.0.240.23
4	10.0.240.24/29	10.0.240.25 – 10.0.240.30	10.0.240.31
5	10.0.240.32/29	10.0.240.33 – 10.0.240.38	10.0.240.39
6	10.0.240.40/29	10.0.240.41 – 10.0.240.46	10.0.240.47
7	10.0.240.48/29	10.0.240.49 – 10.0.240.54	10.0.240.55
8	10.0.240.56/29	10.0.240.57 – 10.0.240.62	10.0.240.63
9	10.0.240.64/29	10.0.240.65 – 10.0.240.70	10.0.240.71
10	10.0.240.72/29	10.0.240.73 – 10.0.240.78	10.0.240.79
11	10.0.240.80/29	10.0.240.81 – 10.0.240.86	10.0.240.87
12	10.0.240.88/29	10.0.240.89 – 10.0.240.94	10.0.240.95
13	10.0.240.96/29	10.0.240.97 – 10.0.240.102	10.0.240.103
14	10.0.240.104/29	10.0.240.105 – 10.0.240.110	10.0.240.111
15	10.0.240.112/29	10.0.240.113 – 10.0.240.118	10.0.240.119
16	10.0.240.120/29	10.0.240.121 – 10.0.240.126	10.0.240.127
17	10.0.240.128/29	10.0.240.129 – 10.0.240.134	10.0.240.135
18	10.0.240.136/29	10.0.240.137 – 10.0.240.142	10.0.240.143
19	10.0.240.144/29	10.0.240.145 – 10.0.240.150	10.0.240.151
20	10.0.240.152/29	10.0.240.153 – 10.0.240.158	10.0.240.159
21	10.0.240.160/29	10.0.240.161 – 10.0.240.166	10.0.240.167
22	10.0.240.168/29	10.0.240.169 – 10.0.240.174	10.0.240.175
23	10.0.240.176/29	10.0.240.177 – 10.0.240.182	10.0.240.183
24	10.0.240.184/29	10.0.240.185 – 10.0.240.190	10.0.240.191
25	10.0.240.192/29	10.0.240.193 – 10.0.240.198	10.0.240.199
26	10.0.240.200/29	10.0.240.201 – 10.0.240.206	10.0.240.207
27	10.0.240.208/29	10.0.240.209 – 10.0.240.214	10.0.240.215
28	10.0.240.216/29	10.0.240.217 – 10.0.240.222	10.0.240.223
29	10.0.240.224/29	10.0.240.225 – 10.0.240.230	10.0.240.231
30	10.0.240.232/29	10.0.240.233 – 10.0.240.238	10.0.240.239
31	10.0.240.240/29	10.0.240.241 – 10.0.240.246	10.0.240.247
32	10.0.240.248/29	10.0.240.249 – 10.0.240.254	10.0.240.255
33	10.0.241.0/29	10.0.241.1 – 10.0.241.6	10.0.241.7
34	10.0.241.8/29	10.0.241.9 – 10.0.241.14	10.0.241.15
35	10.0.241.16/29	10.0.241.17 – 10.0.241.22	10.0.241.23
36	10.0.241.24/29	10.0.241.25 – 10.0.241.30	10.0.241.31
37	10.0.241.32/29	10.0.241.33 – 10.0.241.38	10.0.241.39
38	10.0.241.40/29	10.0.241.41 – 10.0.241.46	10.0.241.47
39	10.0.241.48/29	10.0.241.49 – 10.0.241.54	10.0.241.55
40	10.0.241.56/29	10.0.241.57 – 10.0.241.62	10.0.241.63
41	10.0.241.64/29	10.0.241.65 – 10.0.241.70	10.0.241.71
42	10.0.241.72/29	10.0.241.73 – 10.0.241.78	10.0.241.79
43	10.0.241.80/29	10.0.241.81 – 10.0.241.86	10.0.241.87
44	10.0.241.88/29	10.0.241.89 – 10.0.241.94	10.0.241.95
45	10.0.241.96/29	10.0.241.97 – 10.0.241.102	10.0.241.103
46	10.0.241.104/29	10.0.241.105 – 10.0.241.110	10.0.241.111
47	10.0.241.112/29	10.0.241.113 – 10.0.241.118	10.0.241.119
48	10.0.241.120/29	10.0.241.121 – 10.0.241.126	10.0.241.127
49	10.0.241.128/29	10.0.241.129 – 10.0.241.134	10.0.241.135
50	10.0.241.136/29	10.0.241.137 – 10.0.241.142	10.0.241.143
51	10.0.241.144/29	10.0.241.145 – 10.0.241.150	10.0.241.151
52	10.0.241.152/29	10.0.241.153 – 10.0.241.158	10.0.241.159
53	10.0.241.160/29	10.0.241.161 – 10.0.241.166	10.0.241.167
54	10.0.241.168/29	10.0.241.169 – 10.0.241.174	10.0.241.175
55	10.0.241.176/29	10.0.241.177 – 10.0.241.182	10.0.241.183
56	10.0.241.184/29	10.0.241.185 – 10.0.241.190	10.0.241.191
57	10.0.241.192/29	10.0.241.193 – 10.0.241.198	10.0.241.199
58	10.0.241.200/29	10.0.241.201 – 10.0.241.206	10.0.241.207
59	10.0.241.208/29	10.0.241.209 – 10.0.241.214	10.0.241.215
60	10.0.241.216/29	10.0.241.217 – 10.0.241.222	10.0.241.223
61	10.0.241.224/29	10.0.241.225 – 10.0.241.230	10.0.241.231
62	10.0.241.232/29	10.0.241.233 – 10.0.241.238	10.0.241.239
63	10.0.241.240/29	10.0.241.241 – 10.0.241.246	10.0.241.247
64	10.0.241.248/29	10.0.241.249 – 10.0.241.254	10.0.241.255
65	10.0.242.0/29	10.0.242.1 – 10.0.242.6	10.0.242.7
66	10.0.242.8/29	10.0.242.9 – 10.0.242.14	10.0.242.15
67	10.0.242.16/29	10.0.242.17 – 10.0.242.22	10.0.242.23
68	10.0.242.24/29	10.0.242.25 – 10.0.242.30	10.0.242.31
69	10.0.242.32/29	10.0.242.33 – 10.0.242.38	10.0.242.39
70	10.0.242.40/29	10.0.242.41 – 10.0.242.46	10.0.242.47
71	10.0.242.48/29	10.0.242.49 – 10.0.242.54	10.0.242.55
72	10.0.242.56/29	10.0.242.57 – 10.0.242.62	10.0.242.63
73	10.0.242.64/29	10.0.242.65 – 10.0.242.70	10.0.242.71
74	10.0.242.72/29	10.0.242.73 – 10.0.242.78	10.0.242.79
75	10.0.242.80/29	10.0.242.81 – 10.0.242.86	10.0.242.87
76	10.0.242.88/29	10.0.242.89 – 10.0.242.94	10.0.242.95
77	10.0.242.96/29	10.0.242.97 – 10.0.242.102	10.0.242.103
78	10.0.242.104/29	10.0.242.105 – 10.0.242.110	10.0.242.111
79	10.0.242.112/29	10.0.242.113 – 10.0.242.118	10.0.242.119
80	10.0.242.120/29	10.0.242.121 – 10.0.242.126	10.0.242.127
81	10.0.242.128/29	10.0.242.129 – 10.0.242.134	10.0.242.135
82	10.0.242.136/29	10.0.242.137 – 10.0.242.142	10.0.242.143
83	10.0.242.144/29	10.0.242.145 – 10.0.242.150	10.0.242.151
84	10.0.242.152/29	10.0.242.153 – 10.0.242.158	10.0.242.159
85	10.0.242.160/29	10.0.242.161 – 10.0.242.166	10.0.242.167
86	10.0.242.168/29	10.0.242.169 – 10.0.242.174	10.0.242.175
87	10.0.242.176/29	10.0.242.177 – 10.0.242.182	10.0.242.183
88	10.0.242.184/29	10.0.242.185 – 10.0.242.190	10.0.242.191
89	10.0.242.192/29	10.0.242.193 – 10.0.242.198	10.0.242.199
90	10.0.242.200/29	10.0.242.201 – 10.0.242.206	10.0.242.207
91	10.0.242.208/29	10.0.242.209 – 10.0.242.214	10.0.242.215
92	10.0.242.216/29	10.0.242.217 – 10.0.242.222	10.0.242.223
93	10.0.242.224/29	10.0.242.225 – 10.0.242.230	10.0.242.231
94	10.0.242.232/29	10.0.242.233 – 10.0.242.238	10.0.242.239
95	10.0.242.240/29	10.0.242.241 – 10.0.242.246	10.0.242.247
96	10.0.242.248/29	10.0.242.249 – 10.0.242.254	10.0.242.255
97	10.0.243.0/29	10.0.243.1 – 10.0.243.6	10.0.243.7
98	10.0.243.8/29	10.0.243.9 – 10.0.243.14	10.0.243.15
99	10.0.243.16/29	10.0.243.17 – 10.0.243.22	10.0.243.23
100	10.0.243.24/29	10.0.243.25 – 10.0.243.30	10.0.243.31
101	10.0.243.32/29	10.0.243.33 – 10.0.243.38	10.0.243.39
102	10.0.243.40/29	10.0.243.41 – 10.0.243.46	10.0.243.47
103	10.0.243.48/29	10.0.243.49 – 10.0.243.54	10.0.243.55
104	10.0.243.56/29	10.0.243.57 – 10.0.243.62	10.0.243.63
105	10.0.243.64/29	10.0.243.65 – 10.0.243.70	10.0.243.71
106	10.0.243.72/29	10.0.243.73 – 10.0.243.78	10.0.243.79
107	10.0.243.80/29	10.0.243.81 – 10.0.243.86	10.0.243.87
108	10.0.243.88/29	10.0.243.89 – 10.0.243.94	10.0.243.95
109	10.0.243.96/29	10.0.243.97 – 10.0.243.102	10.0.243.103
110	10.0.243.104/29	10.0.243.105 – 10.0.243.110	10.0.243.111
111	10.0.243.112/29	10.0.243.113 – 10.0.243.118	10.0.243.119
112	10.0.243.120/29	10.0.243.121 – 10.0.243.126	10.0.243.127
113	10.0.243.128/29	10.0.243.129 – 10.0.243.134	10.0.243.135
114	10.0.243.136/29	10.0.243.137 – 10.0.243.142	10.0.243.143
115	10.0.243.144/29	10.0.243.145 – 10.0.243.150	10.0.243.151
116	10.0.243.152/29	10.0.243.153 – 10.0.243.158	10.0.243.159
117	10.0.243.160/29	10.0.243.161 – 10.0.243.166	10.0.243.167
118	10.0.243.168/29	10.0.243.169 – 10.0.243.174	10.0.243.175
119	10.0.243.176/29	10.0.243.177 – 10.0.243.182	10.0.243.183
120	10.0.243.184/29	10.0.243.185 – 10.0.243.190	10.0.243.191
121	10.0.243.192/29	10.0.243.193 – 10.0.243.198	10.0.243.199
122	10.0.243.200/29	10.0.243.201 – 10.0.243.206	10.0.243.207
123	10.0.243.208/29	10.0.243.209 – 10.0.243.214	10.0.243.215
124	10.0.243.216/29	10.0.243.217 – 10.0.243.222	10.0.243.223
125	10.0.243.224/29	10.0.243.225 – 10.0.243.230	10.0.243.231
126	10.0.243.232/29	10.0.243.233 – 10.0.243.238	10.0.243.239
127	10.0.243.240/29	10.0.243.241 – 10.0.243.246	10.0.243.247
128	10.0.243.248/29	10.0.243.249 – 10.0.243.254	10.0.243.255
129	10.0.244.0/29	10.0.244.1 – 10.0.244.6	10.0.244.7
130	10.0.244.8/29	10.0.244.9 – 10.0.244.14	10.0.244.15
131	10.0.244.16/29	10.0.244.17 – 10.0.244.22	10.0.244.23
132	10.0.244.24/29	10.0.244.25 – 10.0.244.30	10.0.244.31
133	10.0.244.32/29	10.0.244.33 – 10.0.244.38	10.0.244.39
134	10.0.244.40/29	10.0.244.41 – 10.0.244.46	10.0.244.47
135	10.0.244.48/29	10.0.244.49 – 10.0.244.54	10.0.244.55
136	10.0.244.56/29	10.0.244.57 – 10.0.244.62	10.0.244.63
137	10.0.244.64/29	10.0.244.65 – 10.0.244.70	10.0.244.71
138	10.0.244.72/29	10.0.244.73 – 10.0.244.78	10.0.244.79
139	10.0.244.80/29	10.0.244.81 – 10.0.244.86	10.0.244.87
140	10.0.244.88/29	10.0.244.89 – 10.0.244.94	10.0.244.95
141	10.0.244.96/29	10.0.244.97 – 10.0.244.102	10.0.244.103
142	10.0.244.104/29	10.0.244.105 – 10.0.244.110	10.0.244.111
143	10.0.244.112/29	10.0.244.113 – 10.0.244.118	10.0.244.119
144	10.0.244.120/29	10.0.244.121 – 10.0.244.126	10.0.244.127
145	10.0.244.128/29	10.0.244.129 – 10.0.244.134	10.0.244.135
146	10.0.244.136/29	10.0.244.137 – 10.0.244.142	10.0.244.143
147	10.0.244.144/29	10.0.244.145 – 10.0.244.150	10.0.244.151
148	10.0.244.152/29	10.0.244.153 – 10.0.244.158	10.0.244.159
149	10.0.244.160/29	10.0.244.161 – 10.0.244.166	10.0.244.167
150	10.0.244.168/29	10.0.244.169 – 10.0.244.174	10.0.244.175
151	10.0.244.176/29	10.0.244.177 – 10.0.244.182	10.0.244.183
152	10.0.244.184/29	10.0.244.185 – 10.0.244.190	10.0.244.191
153	10.0.244.192/29	10.0.244.193 – 10.0.244.198	10.0.244.199
154	10.0.244.200/29	10.0.244.201 – 10.0.244.206	10.0.244.207
155	10.0.244.208/29	10.0.244.209 – 10.0.244.214	10.0.244.215
156	10.0.244.216/29	10.0.244.217 – 10.0.244.222	10.0.244.223
157	10.0.244.224/29	10.0.244.225 – 10.0.244.230	10.0.244.231
158	10.0.244.232/29	10.0.244.233 – 10.0.244.238	10.0.244.239
159	10.0.244.240/29	10.0.244.241 – 10.0.244.246	10.0.244.247
160	10.0.244.248/29	10.0.244.249 – 10.0.244.254	10.0.244.255
161	10.0.245.0/29	10.0.245.1 – 10.0.245.6	10.0.245.7
162	10.0.245.8/29	10.0.245.9 – 10.0.245.14	10.0.245.15
163	10.0.245.16/29	10.0.245.17 – 10.0.245.22	10.0.245.23
164	10.0.245.24/29	10.0.245.25 – 10.0.245.30	10.0.245.31
165	10.0.245.32/29	10.0.245.33 – 10.0.245.38	10.0.245.39
166	10.0.245.40/29	10.0.245.41 – 10.0.245.46	10.0.245.47
167	10.0.245.48/29	10.0.245.49 – 10.0.245.54	10.0.245.55
168	10.0.245.56/29	10.0.245.57 – 10.0.245.62	10.0.245.63
169	10.0.245.64/29	10.0.245.65 – 10.0.245.70	10.0.245.71
170	10.0.245.72/29	10.0.245.73 – 10.0.245.78	10.0.245.79
171	10.0.245.80/29	10.0.245.81 – 10.0.245.86	10.0.245.87
172	10.0.245.88/29	10.0.245.89 – 10.0.245.94	10.0.245.95
173	10.0.245.96/29	10.0.245.97 – 10.0.245.102	10.0.245.103
174	10.0.245.104/29	10.0.245.105 – 10.0.245.110	10.0.245.111
175	10.0.245.112/29	10.0.245.113 – 10.0.245.118	10.0.245.119
176	10.0.245.120/29	10.0.245.121 – 10.0.245.126	10.0.245.127
177	10.0.245.128/29	10.0.245.129 – 10.0.245.134	10.0.245.135
178	10.0.245.136/29	10.0.245.137 – 10.0.245.142	10.0.245.143
179	10.0.245.144/29	10.0.245.145 – 10.0.245.150	10.0.245.151
180	10.0.245.152/29	10.0.245.153 – 10.0.245.158	10.0.245.159
181	10.0.245.160/29	10.0.245.161 – 10.0.245.166	10.0.245.167
182	10.0.245.168/29	10.0.245.169 – 10.0.245.174	10.0.245.175
183	10.0.245.176/29	10.0.245.177 – 10.0.245.182	10.0.245.183
184	10.0.245.184/29	10.0.245.185 – 10.0.245.190	10.0.245.191
185	10.0.245.192/29	10.0.245.193 – 10.0.245.198	10.0.245.199
186	10.0.245.200/29	10.0.245.201 – 10.0.245.206	10.0.245.207
187	10.0.245.208/29	10.0.245.209 – 10.0.245.214	10.0.245.215
188	10.0.245.216/29	10.0.245.217 – 10.0.245.222	10.0.245.223
189	10.0.245.224/29	10.0.245.225 – 10.0.245.230	10.0.245.231
190	10.0.245.232/29	10.0.245.233 – 10.0.245.238	10.0.245.239
191	10.0.245.240/29	10.0.245.241 – 10.0.245.246	10.0.245.247
192	10.0.245.248/29	10.0.245.249 – 10.0.245.254	10.0.245.255
193	10.0.246.0/29	10.0.246.1 – 10.0.246.6	10.0.246.7
194	10.0.246.8/29	10.0.246.9 – 10.0.246.14	10.0.246.15
195	10.0.246.16/29	10.0.246.17 – 10.0.246.22	10.0.246.23
196	10.0.246.24/29	10.0.246.25 – 10.0.246.30	10.0.246.31
197	10.0.246.32/29	10.0.246.33 – 10.0.246.38	10.0.246.39
198	10.0.246.40/29	10.0.246.41 – 10.0.246.46	10.0.246.47
199	10.0.246.48/29	10.0.246.49 – 10.0.246.54	10.0.246.55
200	10.0.246.56/29	10.0.246.57 – 10.0.246.62	10.0.246.63
201	10.0.246.64/29	10.0.246.65 – 10.0.246.70	10.0.246.71
202	10.0.246.72/29	10.0.246.73 – 10.0.246.78	10.0.246.79
203	10.0.246.80/29	10.0.246.81 – 10.0.246.86	10.0.246.87
204	10.0.246.88/29	10.0.246.89 – 10.0.246.94	10.0.246.95
205	10.0.246.96/29	10.0.246.97 – 10.0.246.102	10.0.246.103
206	10.0.246.104/29	10.0.246.105 – 10.0.246.110	10.0.246.111
207	10.0.246.112/29	10.0.246.113 – 10.0.246.118	10.0.246.119
208	10.0.246.120/29	10.0.246.121 – 10.0.246.126	10.0.246.127
209	10.0.246.128/29	10.0.246.129 – 10.0.246.134	10.0.246.135
210	10.0.246.136/29	10.0.246.137 – 10.0.246.142	10.0.246.143
211	10.0.246.144/29	10.0.246.145 – 10.0.246.150	10.0.246.151
212	10.0.246.152/29	10.0.246.153 – 10.0.246.158	10.0.246.159
213	10.0.246.160/29	10.0.246.161 – 10.0.246.166	10.0.246.167
214	10.0.246.168/29	10.0.246.169 – 10.0.246.174	10.0.246.175
215	10.0.246.176/29	10.0.246.177 – 10.0.246.182	10.0.246.183
216	10.0.246.184/29	10.0.246.185 – 10.0.246.190	10.0.246.191
217	10.0.246.192/29	10.0.246.193 – 10.0.246.198	10.0.246.199
218	10.0.246.200/29	10.0.246.201 – 10.0.246.206	10.0.246.207
219	10.0.246.208/29	10.0.246.209 – 10.0.246.214	10.0.246.215
220	10.0.246.216/29	10.0.246.217 – 10.0.246.222	10.0.246.223
221	10.0.246.224/29	10.0.246.225 – 10.0.246.230	10.0.246.231
222	10.0.246.232/29	10.0.246.233 – 10.0.246.238	10.0.246.239
223	10.0.246.240/29	10.0.246.241 – 10.0.246.246	10.0.246.247
224	10.0.246.248/29	10.0.246.249 – 10.0.246.254	10.0.246.255
225	10.0.247.0/29	10.0.247.1 – 10.0.247.6	10.0.247.7
226	10.0.247.8/29	10.0.247.9 – 10.0.247.14	10.0.247.15
227	10.0.247.16/29	10.0.247.17 – 10.0.247.22	10.0.247.23
228	10.0.247.24/29	10.0.247.25 – 10.0.247.30	10.0.247.31
229	10.0.247.32/29	10.0.247.33 – 10.0.247.38	10.0.247.39
230	10.0.247.40/29	10.0.247.41 – 10.0.247.46	10.0.247.47
231	10.0.247.48/29	10.0.247.49 – 10.0.247.54	10.0.247.55
232	10.0.247.56/29	10.0.247.57 – 10.0.247.62	10.0.247.63
233	10.0.247.64/29	10.0.247.65 – 10.0.247.70	10.0.247.71
234	10.0.247.72/29	10.0.247.73 – 10.0.247.78	10.0.247.79
235	10.0.247.80/29	10.0.247.81 – 10.0.247.86	10.0.247.87
236	10.0.247.88/29	10.0.247.89 – 10.0.247.94	10.0.247.95
237	10.0.247.96/29	10.0.247.97 – 10.0.247.102	10.0.247.103
238	10.0.247.104/29	10.0.247.105 – 10.0.247.110	10.0.247.111
239	10.0.247.112/29	10.0.247.113 – 10.0.247.118	10.0.247.119
240	10.0.247.120/29	10.0.247.121 – 10.0.247.126	10.0.247.127
241	10.0.247.128/29	10.0.247.129 – 10.0.247.134	10.0.247.135
242	10.0.247.136/29	10.0.247.137 – 10.0.247.142	10.0.247.143
243	10.0.247.144/29	10.0.247.145 – 10.0.247.150	10.0.247.151
244	10.0.247.152/29	10.0.247.153 – 10.0.247.158	10.0.247.159
245	10.0.247.160/29	10.0.247.161 – 10.0.247.166	10.0.247.167
246	10.0.247.168/29	10.0.247.169 – 10.0.247.174	10.0.247.175
247	10.0.247.176/29	10.0.247.177 – 10.0.247.182	10.0.247.183
248	10.0.247.184/29	10.0.247.185 – 10.0.247.190	10.0.247.191
249	10.0.247.192/29	10.0.247.193 – 10.0.247.198	10.0.247.199
250	10.0.247.200/29	10.0.247.201 – 10.0.247.206	10.0.247.207
251	10.0.247.208/29	10.0.247.209 – 10.0.247.214	10.0.247.215
252	10.0.247.216/29	10.0.247.217 – 10.0.247.222	10.0.247.223
253	10.0.247.224/29	10.0.247.225 – 10.0.247.230	10.0.247.231
254	10.0.247.232/29	10.0.247.233 – 10.0.247.238	10.0.247.239
255	10.0.247.240/29	10.0.247.241 – 10.0.247.246	10.0.247.247
256	10.0.247.248/29	10.0.247.249 – 10.0.247.254	10.0.247.255

01 / table

IPv4 CIDR prefix table.

Click a prefix longer than your network to split it into subnets.

prefix	subnet mask	addresses	hosts	in your /21
/0	0.0.0.0	4,294,967,296	4,294,967,294	-
/1	128.0.0.0	2,147,483,648	2,147,483,646	-
/2	192.0.0.0	1,073,741,824	1,073,741,822	-
/3	224.0.0.0	536,870,912	536,870,910	-
/4	240.0.0.0	268,435,456	268,435,454	-
/5	248.0.0.0	134,217,728	134,217,726	-
/6	252.0.0.0	67,108,864	67,108,862	-
/7	254.0.0.0	33,554,432	33,554,430	-
/8	255.0.0.0	16,777,216	16,777,214	-
/9	255.128.0.0	8,388,608	8,388,606	-
/10	255.192.0.0	4,194,304	4,194,302	-
/11	255.224.0.0	2,097,152	2,097,150	-
/12	255.240.0.0	1,048,576	1,048,574	-
/13	255.248.0.0	524,288	524,286	-
/14	255.252.0.0	262,144	262,142	-
/15	255.254.0.0	131,072	131,070	-
/16	255.255.0.0	65,536	65,534	-
/17	255.255.128.0	32,768	32,766	-
/18	255.255.192.0	16,384	16,382	-
/19	255.255.224.0	8,192	8,190	-
/20	255.255.240.0	4,096	4,094	-
/21	255.255.248.0	2,048	2,046	1
/22	255.255.252.0	1,024	1,022	2 split →
/23	255.255.254.0	512	510	4 split →
/24	255.255.255.0	256	254	8 split →
/25	255.255.255.128	128	126	16 split →
/26	255.255.255.192	64	62	32 split →
/27	255.255.255.224	32	30	64 split →
/28	255.255.255.240	16	14	128 split →
/29	255.255.255.248	8	6	256 split →
/30	255.255.255.252	4	2	512 split →
/31	255.255.255.254	2	2	1,024 split →
/32	255.255.255.255	1	1	2,048 split →

02 / faq

About this calculator.

How do I use this subnet calculator?

▼

Type an IP address followed by a prefix, like 192.168.1.10/24, or by a subnet mask, like 192.168.1.10 255.255.255.0. Without a prefix it uses /24. Click a row in the table to split the network into smaller subnets.

Why are usable hosts always 2 fewer?

▼

The first address in a subnet is the network address and the last is the broadcast address, so neither can go to a device. The exceptions are /31 (point-to-point links, RFC 3021) and /32 (a single address), which use every address.

Can I use it from a terminal?

▼

Yes. curl 'ipku.in/en/tools/ipv4-subnet-calculator?q=192.168.1.10/24' returns the result as plain text.

Learn how to work it out →